Scientists have discovered hundreds of hidden galaxies behind the Milky Way using a radio telescope at the Parkes Observatory in western New South Wales.

The newly-discovered galaxies are 250 million light-years away -- close neighbours, in galactic terms -- and will only get closer, as researchers claim they are pulling our own galaxy, the Milky Way, towards it.

The University of Western Australia announced the astronomic revelation on Wednesday, with the Australian scientists part of a large global team from the International Centre for Radio Astronomy Research (ICRAR), including researchers from the U.S, South Africa and the Netherlands.

Professor Lister Staveley-Smith, who led the team in Australia, said more than 800 galaxies were found using the Parkes radio telescope, one third of which had never been seen before.

“The Milky Way is very beautiful of course and it’s very interesting to study our own galaxy but it completely blocks out the view of the more distant galaxies behind it,” said Professor Staveley-Smith in a statement released by the University of Western Australia.

"An average galaxy contains 100 billion stars, so finding hundreds of new galaxies hidden behind the Milky Way points to a lot of mass we didn't know about until now."

The discovery also helps explain an anomaly of our own galaxy -- that is, why it is moving in that direction.

“We know that in this region there are a few very large collections of galaxies we call clusters or superclusters, and our whole Milky Way is moving towards them at more than two million kilometres per hour," Professor Staveley-Smith said.

The new discovery was published in the Astronomical Journal on Wednesday.